Providing Technical Invariance of Crystal Oscillators Based on Autonomising Dual-Loop PLL System

In this paper, a promising functional and algorithmic method for ensuring technical invariance of quartz crystal oscillators (XO) based on the autonomising dual-loop PLL systems was developed. The advantages of using multi-frequency excitation mode for quartz crystal resonator (QR) were shown in order to improve accuracy when identifying its current state under the influence of destabilizing factors. The uses of PLL systems required to compensate for temperature and vibration of destabilizing effects in QR when combining its stabilizing and measuring functions were highlighted.